1. Field of the Invention
The present invention relates to a capacitive rain sensor for a motor vehicle, including a printed circuit board with sensor structures laminated thereon and with electronic components.
2. Description of the Background Art
One of the convenience functions in modern motor vehicles is automatic, as-needed activation of the windshield wipers. This results in the need to detect rain on the windshield, for which purpose are known capacitive rain sensors, among other solutions. For example, German patent DE 101 52 998 C2 describes a sensor unit in which a capacitive rain sensor, a condensation sensor, and an analysis unit are arranged on a common circuit board. The rain sensor here has two conductive traces that are electrically separate from one another and that form a capacitor whose capacitance changes as a function of the quantity of rain present in the stray field.